Speaking to a meeting of the Conservative Councillors' Association on Friday, Matt Hancock MP will say that the Localism Act gives Councils the opportunity to act to ban full time officials.

The legislation requires councillors to declare financial interests, and allows for them to be disbarred from voting where they have a conflict of interests.

Mr Hancock will argue that this means union-supported Councillors will not lawfully be able to vote for public subsidy for unions. He will say: “I am not against unions, but like most people I think unions should be paid for by union members.

“Public money should pay for public services not [full time officials]. The Localism Act is the chance for all Councils to end this unfairness and ensure taxpayers' money is spent on services not subsidies.”

Mr Hancock will add: “Taxpayer subsidy of unions exploded under Labour, to the point that the TUC now receives fully three quarters of its funding from the public purse, runs a surplus of £40 million a year and is sitting on top of £1billion of assets.”

In December, Prime Minister David Cameron said that taxpayers’ money to fund trade union activity “cannot be sustained, either morally or economically”.

He was speaking after a report from the TaxPayers' Alliance suggested that Mr Cameron also threw his backing behind a new campaign group which an estimated £113million of taxpayers' money was used to pay the salaries of union officials in the workplace in just one year.